The present invention relates generally to a method of providing a heat pipe with an evacuated space above a quantity of vaporizable fluid. The invention provides specifically for a method of providing an evacuated space above a predetermined quantity of vaporizable fluid in a heat pipe to thus permit the optimum transfer of heat between opposite ends of the heat pipe by a continuous process of evaporation and condensation of the fluid. A novel feature of the invention provides for the supply of a predetermined quantity of fluid to a heat pipe whereby fluid may be added to or taken away from a reservoir of fluid in the heat pipe, or the fluid may be completely changed to provide for the specific heat transfer qualities required.
In known apparatus adapted to utilize heat pipes for the regenerative transfer of heat between hot and cold zones, the heat pipes are charged with a vaporizable fluid that is intended to be present for the life of the tube. There is no provision for changing or even adding fluid thereto to meet the requirements of a specific process.
U.S. Pat. No. 1,725,906 of Aug. 27, 1929, U.S. Pat. No. 2,746,725 of Mar. 22, 1956, and U.S. Pat. No. 4,183,399 of Jan. 15, 1980, are but examples of conventional heat pipe apparatus in which the heat pipes disclosed are standard tubular elements adapted to be supplied with a single charge of vaporizable fluid.